Starter for internal-combustion engines.



F. w. scuwmm. STARTER FOR INTERNAL COMBUSTION ENGINES. APPLICATION FILED FEB- 19, I916- Patehted Feb. 13,1917. 3 EEEEEEEEEEEE I F. W. SCHWINN.

STARTER FOR INTERNAL COMBUSTION ENGINES. APPLICATION FILED FEB- 19.1916.

3 SHEETS-SHEET 2.

Patented Feb. 13, 1917.

F. W. SCHWINN. STARTER FOR INTERNAL COMBUSTION ENGINES. APPLICATION FILED FEB-19, 1916- 3,215,877 Patented Feb. 13,1917.

3 SHEETSSHEET 3- FRANK W. SCHWINN, 0F CHICAGG, ILLINOIS.

- I STARTER FOB IN'EEBNAL-COMBUSTIUN-ENGINES.

inmate.

Specification of Letters Patent.

Application filed February to, me. Serial m. 79,256.

To all whom it may concern:

Be it known that I, FRANK W. SCHWINN, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented anew and usefullmprovement in Starters for Internal-Combustion Engines, of which the following is a specification. V

My invention relates to certain new and useful improvements in starting mechanism for internal-combustion engines. The object of the invention is to provide a simple and eihcient combination of mechanisms by which an internal-combustion engine may be cranked for starting the same, the arrangement being such that the initial movement of the cranking mechanism acts to relieve the compression in the engine cylinder, or cylinders, to permit a quick initial acceleration. The invention is particularly adaptable for internal combustion engines of the type used on motorcycles. For the purpose of making the invention more clear, I have illustrated a specific construction of apparatus embodying thesame in the accompanying drawings, in which Figure 1 is a side elevation of the central portion of a motorcycle frame, showing an internal combustion engine mounted therein, and connected with my improved starter;

Fig; 2 is an enlarged detailed side elevation of'the starter mechanism in inoperative position;

Fig. 3 is a diagrammatic'view illustrating the action of the starter,

Fig. .4 is a similar view showing a further advanced position of the starting lever.

Fig. 5 is an enlarged side elevation of the lower portion of the motor, showing its connection with the transmission. Fig. 6 is an enlarged vertical section showing the compression relief mechanism; and Fig. 7 is a section on the line 7 of Fig. 5 and showing the clutch connection between the starting gear and its shaft.

Referring more particularly to the drawm s th frame of the motorcycle, the. frame shown being of the open type carrying a twin-cylinder internal-combustion engine 11 and a'transmission frame 12 at its bottom ortion in th relation shown. Within the rame 12 there is adjustably mounted a gear box 13, the adjustment being provided by slots 14.- arranged longitudmally of the frame 12 so that the gear box may be moved the numeral 10 designates in general toward and away from the 'motorfor the purpose of tightening or loosening the chain" which commonly connects these members. This construction is old and well known in the art and I willtherefore .describe the parts thereof only in so far as they cooperate with my invention.

One of the shaft members 15 of the transmission gearing, preferably the shaft-member which is directly connected with the motor as by the chain 15 shown in Fig. 5, is extended out of the gear box 13, and is provided on its extending end with a gear wheel 16. A shaft l'l mounted parallel with the shaft 15 and carried in journals in the gear box 13- has a sector gear 18 arranged in operative relation to the gear 16, so as to mesh with the teeth of the latter and thereby drive the shaft 15 and through it the crank-shaft of the motor. The far end of the shaft 17 (as viewed from Fig. 1), has mounted thereon a lever 19 which may be provided with a folding crank pin or a similar device by which the lever may be actu ated by the hand or foot of'the operator to rock the shaft, this. lever being normally held in the position shown in Fig. 1 by a spring, counter-weight or other device, not shown. I

Formed integrally with the hub of the sector ear 18 or otherwise secured to the projecting end of the rock-shaft 17, there is a cam member 20 having a protuberance thereon which is adapted to engage and lift an angular foot carried by a lever 21 jour- .naled upon a stud mounted in the gear-box 13. llhe lever 21 has a link 22 connected therewith by which the motion of the leveris communicated to a compression relief lever 23 on the internal combustion engine.

Patented Feb. 13, 121% As shown in Fig.6 the. com ressio'n relief lever 23 has a cam-shaped en 25 which engages a spring-held plunger 26, the conical lower end of which is adapted to be forced between the bell-crank members 27 by which the cam 28 operates the valves of the engine I cylinders. By rocking the lever 23 the connections described serve to elevate on'e valve of each of the two engine cylinders above its seatfwhereby the compression is relieved. Since it is designed that the gear-box 13 be moved as a unittoward and away from the engine 11, it is desirable that the link 22 be provided with a turn-buckle 24 therein,

by which its length maybe altered to'conform to the adjustment of the gear-box.

The operation of my improved starter will be best understood from Figs. 2, 3 ands, in which the relation of the parts for three different positions of the starting lever are shown. From these figures it will be noted that as the shaft 17 is rocked in a counterclockwise direction the protuberance of the cam 20 will engage the toe or foot member of the lever 21 rocking the latter to the right, as viewed in the drawings, will maintain. the lever in its tilted position for a certain predetermined angular movement of the shaft 17, and will then permit the lever to return to its normal position, as the cam protuberance passes out from under its foot. As is clearly shown in Figs. 2, 3 and 4:, the opposite faces of the cam protuberance are of equal inclination as are the opposite faces of the lever foot with which these faces cooperate. The mechanism is reversible therefore, that is, the cam may ride beneath the foot to shift the lever 21 when moved in the .starting or counter-clockwise direction, indicated by the arrows in, Figs. 2, 3 and 4, and also when turning to the normal position shown in Fig. 1.

For the purposes of making clear the advantages of my improved construction 1 will describe in some detail the procedure employed in starting the engine by my mechanism, though it is believed that the operation of the mechanism will have been made clear from the description of its parts. Assuming that the elements of the mechanism are in the position shown in Fig. 1, and that it is desired to start the engine, force will be applied to the lever 19 as by kicking or pushing the same with the foot in a wellknown manner, thereby rocking the shaft 17 in a counter-clockwise direction. It will be noted that in the normal position of the parts, the sector gear 18 is out of en agement with the gear Wheel 16, sothat the ever 19 may have a certain predetermined free movement before these members engage. This is of advantage in that itpermits the rock-shaft 17 and its connected parts, as

well as the footof the operator, to gain considerable momentum before any resisting force is interposed. During-this first free movement of the shaft 17, the lever 21 will have been oscillated, moving it from the position shown in Figs. 1 or 2, to the position shown in Fig. 3, thereby actuating the compression relief devices of the motor through the lever 23 thereon. Approximately at the time that the compression relief devices have reached their operative position, the end of the sector gear 18 engages the gear-wheel 16, and due to the momntum of the parts and the fact that the compression resistance of the enginehas been relieved, the motor crank-shaft will be startedwith a quick jerk. The cam protuberance is preferably formed to provide a short .21, permitting the compression relief devices (which will be spring returned according to the ordinary practice) to come to the inoperative position. The remainder of the stroke of the starting lever 19 will then crank the motor against the resistance of the compression of its cylinders, but since the motor crank-shaft and its fly Wheels have already acquired considerable momentum, this cranking under compression is car-' ried out with the minimum amount of exertion. If the engine is in normal condition an explosion or explosions will occur therein during the intermediate or later portion of the stroke of the starting lever 19. By reason of the fact that such explosion or explosions occur under normal compression instead of under reduced compression, suflicient power will be developed ordinarily to start the motor in normal operation. It will be understood that the gear wheel 16 is provided with an overrunning clutch-of the usual form, such, for instance, as the ratchettoothed clutch shown at 16 in Fig. '7, whereby, when the motor has been started, the gear wheel 16 will stop and may then rotate in the reverse direction as the starting lever and-its connected sector gear are 'returned to the normal position, as shown in Figs. 1 and 2. During such return movement it is clear that the cam will again lift the foot of the lever 21 to throw the com-. pression relief devices into operation, but this movement will be of such short duramethod of operation and advantages obtainable by this construction. It is to be understood, however, that the description referred to is illustrative only, and for the purpose of making the invention more clear, and that it is not to be regarded'as a limitation of the scope of the invention, except in so far as such limitation appears within the terms of the following claims, in which it is' my intention to claim all novelty inherent in my invention as broadly as is permissible in view of the priorart.

What I claim as new and desire to secure by Letters Patent is:

1. The combination with an internal combustion engine having means for reliev- .tion as to have no appreciable effect upon ing the compression in the cylinders thereof,

' theengine in a forward direction for start ing the engine, and'iconnections between .said startlng means and the compression relief mechanism for throwing the latter to operative position by initial movement of the former, and for permitting the compression relief mechanism to return to inoperative position during further operative movement of the starting means.

2. In combination with an internal combustion engine having means for relievingthe compression in the cylinders thereof, of

, means.

3. The combination with an internal com- .bustion engine having means for relieving the compression in the cylinders thereof, of a rock-shaft adapted to be mechanically connected with the said engine for starting the same, a cam carried by the said rock-shaft, a follower mounted inoperative relation to the cam, and connections between the said cam-follower and compression relief means,

the parts being arranged to relieve the compression of the engine during the initial part only of'the operative movement of the said rock-shaft. 1

4:. The combination with an internal com bustion engine having means for relieving the compression in the'cylinder thereof, of a shaft connected with the said engine and having a gear thereon, a rock-shaft mounted parallel with said first-named shaft having a'sector gear thereon adapted to be moved into and out of engagement with said firstnamed ear, a lever for applying power to said roc shaft, a cam carried by said rockshaft, a follower for said cam, connections between said follower and the said compression relief means, the parts being so arranged that the said compression relief means is actuated during the initial part only of the operative movement of said rockshaft. v

' 5. The combination with an internal combustion engme having means-for relieving the compression in the cylinder thereof, of a shaft connected with the said engine and having a gear thereon, a rock-shaft mounted parallel a sector-gear thereon adapted to be moved into and out of engagement with said firstnamed ear, a lever for applying power to said roc -shaft, a cam carried by said rockshaft, a follower for said cam, and connections between said follower and the said compression relief means for operating the latter by movement-of said rock-shaft;

FRANK W. SCHW'INN.

In presence of- A. C. Fisonnn, C. C. BREUEB.

with said first-named shaft having 

